Which of the following best explains why the presence of a catalyst can speed up a…
CHEMISTRY · Single correct · A Level · Chemistry · Kinetics · Kinetics
Problem
Which of the following best explains why the presence of a catalyst can speed up a chemical reaction without altering the reaction’s overall stoichiometry?
(a) The catalyst raises the average kinetic energy of the reactant molecules, so a greater fraction of collisions already exceed the original activation energy.
(b) The catalyst shifts the equilibrium toward products by stabilizing them, causing the forward reaction to proceed more quickly.
(c) The catalyst provides an alternative pathway with a lower activation energy by forming a new intermediate and is regenerated at the end.
(d) The catalyst lowers the reaction’s enthalpy change ΔH, making the products more stable than in the uncatalyzed reaction.